Art of preparing amino arsenobenzenes.



that such is not the ciise.

MQRENZ .A'iDH, 0F MAIQ NISYEIM, AND ALBERT ASSEG-ZEOIRS TU FAB-EWER'KE VOBM. MIKE THE-I=EAIN, GERMANY, A THEM.

so'rmlmim, on HEIDELBERG, enamel, 'rnn LUCIUS & seasonings, on noonsnom ART 0F- PEEE'ARING AMINQ' ARSENQQENZENES; I

No Drawing.

and use the same.

This invention relates to the art of paring smino-nrseno benzenes willpsii'i'licular reference to ehe mpnufacture of his new compound, hexoniino-erseno benzene, the object being to obtain a phormacal compound which combines gerniicide action with relatively low toxicity.

ive have found that ifl-arnino-Zlfi-dinitro benzene-ersinic acid, n compound which has been described in Berle/ ite (fer Deutsciien Chemise/zen Geselisclmft vol. (1912} page 56, is acted on with a reducing agent, a new chemical compound, 3.4.5.3.%'.5-hexazninonrsenohenzene, having valuable therapeutic properties is obtained. The reducing agent for this purpose we have'found, may be acid, for exninple, tin, or stnnnous'chlorid combined with hydrochloric acid. or powder of zinc in conjunction with hydrochloric acid, or it may be the non-aci lcompound sodium hydrnsulfite Since hexamino ursenobenzene contains the amino gi'oups inthe ortho-position and in the meta-position, and it is well-known that ortho-phenylcne (lianiin and metaphenylene cliamin are extremelypoisonous substances, ii: was to be supposed that the present new nrseno derivative would also possess a similar high toxic action and would,

therefore, not be adapted for medicinal use.

lVe have been s'ur rised to find however, l

The following examples, embodying what we consider ,the preferred manner of carrying out the process compr sed in'our invention ore given to fully, disclbse the some.

given lire/by weight, unlessv acid and thereupon gradually mixed ivilh'l Specification of Letters Patent. Application filed March 24, 1913. Serial No. 758,554. I V

cipitnied.

Patented 0c ;.l2, 1915.

parts of pulverized tin while conci'irr ently well stirring the mixture as it proceeds. The product of reduction begins to separate 1mmedietely." After all the tin has been added,

the reaction is hastened by heating the whole over an open flame. The reducing action is at an end when :1 sample of the product dissolves in water to form e clear solution, The Whole is then allowed to cool and lilieprecipitete, which is a double salt of ting-is separated froin'the motherliquor b'v seem lesion, siphoning" or otherwise, end isihen, dissolved in water, suilicienl sods elye {c03 1} being then added to the solution in excess to maintain the tin-oxlds-in colli tion. Thereby the new basic compound isthrown down and is se ernaeil by-l'illcrction. After hsving been thoroughly washed, it is dissolved in double normal hydrochloric acid solution. By thereupon sliding tot soluti on an equal volume of conceiilzrelcdl drochloric acid,the chlorid of the we con. pound, the he):eniino-nrsenobcnzene is lhe precipitate purified bf, washing it successixely with hexanorninl by drochloric acid, alcohol, and. other.

Example 2; .1 parts of the iiinitro'cniino benzene-arsinic acid are gradually added while well stirring the whole, to a solution of parts of crystalline sczmnous chlorid in parts of concentrated hydrochloric acid. Agaimas stated under Example lfche double salt of tin of the new compound is obtained as the product of the reduction. The free new basic compound is then obtained by do composing the said double salt with alkali,

- whereupon she chloricl of the said new basic:

prepared as explained under ture consisting ofequal parts of alcohol and concenlizzitecl hydrochloric acid-and .to this bath are gradually added 30 parts of zinc dust while well stirringf The yellow nitro compound is thereby converted into a flaky- (lnr'k substance which gradually goes into solution. After all the zinc has been added,

the whole is heated over an .open flune until a snr np'le of ithe whole-'lyields a,. yellowishgrreen prcc'i iihit'e cog-adding concentrated hy-' drochli acid 'Tlie eupoh Mfurther qiiantity of 100? parts of concentrated"hydro-,

chloric acid is added to the liquid after the saline has undergone flltration. The whole is then cooled and the precipitated product of-the reduction in the form of a double salt of zinl fi'is separated by siphoning or otherwise. If'is then dissolved in water, and dilute sodawlye is added to the solution,

whereby the new product, the heXamino-arsenobenzene, is obtained which is then obtained as a chlorid by treating it as in the preccdin examples.

In eac of the aboye gxamples the reduc ing agent employed 1S acid and leads to the formation of the corresponding metal double-salt of the new amino-arseno compound.

Instead of 'an acid reducing agent We findthat sodium hydrosulfite may be employed to reduce the startingmaterial, but in this case the immediate roduct of the reaction will be an intermediate product containing sulfur which has the remarkable property .of forming a clear solution with alkali, so that apparently the reduction has not leddirectly to the desired hexamino-arseno compound. However, as has been further found, the salts of the hexaminosarseno compound inay-be' obtained from the sulfurcontainlng intermediate product by treating the same with an acid and preferably heating, whereby sulfurous acid is split off. The process in detail is as follows:

Example 4:; 3 parts of dinitro-amino-benzene-arsmic acid, as above, are dissolved in parts of water to which are added 5.4

parts of double-normal soda-lye (NaOH), and the whole is then gradually mixed with 35 parts of sodium hydrosulfite while vigorously stirring. The solution thereby becomes discolored, and soon a yellow flakyrecipitate separates out of the menstruum,

his phase of the recess is soon. terminated. Thereupon t e precipitate is separated by siphoning, dccantation or otheri wise and washed with some water and it is then suspended in 50 parts of water which ,has been acidulated with 20 parts of tetra- -zene, 1s a'base which is very unstable in a free state, and which rapidly assumes a -dark color on being exposed to the air. It

is readily soluble in dilute acid, but insoluble 1n the usual organic solvents. The chlorid of the new. compound is obtained in the form of a yellowish-green powder readily soluble in water and dilute acids, but insoluble 1n alkalis.

'benzenes, the sub-process which consists in The new compound whether in an uncombined state or in the formof a chlorid is a. powerful germicide having a particularly strong bactericidal action on spirilla.

What 'we claimand desire t secure by Letters Patent is: M

1. In the art of producing amino a sfitmv benzenes, the sub-process which consists in treating 3.5-dinitro-4i-aminobenzene-l-arsi- V nic acid with a reducin agent. "2. In the art of pro ucin amino-arseno benzenes, the sub-process w ich -consist-s in treating 3.5-dinitro-4-aminokuzn'zeneLars: nic acid, with a reducing agent and then treating with alkaline substance to separate the resultant basic compound.

3. In the art of producin' ami'no-arseno- ,benzenes, the sub-process w iich consists in treating 3.5-dinitroi aminobenzene-l-arsinir acid with an acid reducing agent.

4. In the art of producing amino-arsenatreating 3.5-dinitro-4-aminobenzcnvl-arsi-- nic acid with an. acid reducing agent and then'trcating the whole with. an alkaline substance to separate the resultant basic compound. w

5. The process which'cons'zsts in 3.51dinitro l-aminobenicne l-ars is a with a reducing agent,then treating with kaline substance to separate the resultant basic compound, and then treating the latter =1 with acid.

G. The process which consists in treating 3.5 r' dinitrol-aminobenzene l ar'sinic acid with an acid reducing agent, then treating: the whole with an alkaline substance to separate the resultant basic compound, and then treating the latter with acid.

7. As anew composition of matter, a chemical compound comprising the be 3.4.5.3AC5-hexainino-arsenobenacne wi has the property of being readily soluble in dilute acids and insoluble in alkaline solu' tions, and which has strong bactericidal tion.

8. As a new composition of matter, 11-. no chemical compound consisting'in the base 3.4:.d3.4'.5-hexa nino'- arsenobcnzcne, and having the property .Of being readily soluble in dilute acids, insoluble in alkaline solutions and in the usual organic solvents, of .915 rapidly becoming discolored when exposed to the atmosphere, and having strong bac tericidal action.

In testimony whereof we hereunto affix our signatures in the presence of two witnesses.

LORENZ ACI-I. ALBERT ROTI-IMANN.

Witnesses:

.losnrii PFEIFFER, GARRY TILLY. 

